I'm having trouble with the gas gauge on my truck. It reads correctly at empty (which I guess is the important end) because I drained only about 1.5 gallons from the tank after it hit empty. The problem is, when the tank is full, the gauge only reads 3/4 full.
I have done a 12 volt conversion and used a Runtz type voltage reducer on the gauge. I have checked the gauge itself by disconnecting the wire that attaches to the sender and the gauge goes to empty and grounded the wire and the gauge goes to full.
I removed the sender and made sure that everything moves freely.
The rheostat type strip inside the sender hat is what concerns me. I was under the impression that all early Chevy senders were 0 to 30 ohm. I used an adustable resistor in place of the sender and found that I have to provide about 48 ohms to make the gauge read full. The extreme end of the wire wound strip inside the sender hat only provides 42 ohms max.
Also, the factory service manual says it should be a 16 gallon tank, but it only took about 12 gallons to fill. Any ideas?
Heres a link to some pics of the disassembled sender.
http://community.webshots.com/album/569438939DAbzMY?start=36
